A little earlier today, we talked about the new Google+ integration that’s arrived for Play Store reviews. This was one change we saw coming, thanks to some detective work earlier in the month that tore apart a new Play Store APK, looking for clues of new features. Beyond the Google+ addition, that analysis revealed what looked like support for some kind of pre-order system, but that just left us with more questions. After all, we usually think about pre-ordering hardware devices, and while you can buy Nexus devices in the web-based Google Play Store, Google has yet to bring the same functionality to the Android version. Today, the picture on what’s really happening with these pre-orders has started to become clear, thanks to a Google Play help page.

It’s not devices, but books that you’ll soon be able to pre-order through the Play Store app. The process Google describes is very straightforward: find the book you want in the Play Store’s “coming soon” section, hit the pre-order button, and confirm your order. Google won’t actually bill your payment card until the book is finally available for you to read.

We know, it would be a lot more interesting if you could pre-order hardware through the app (or just order hardware at all), but maybe that’s one change that’s still coming to the Store one day.